FAQ's
Can the roof take the increased load?
The average saturated extensive greenroof weighs, at its heaviest, 110kgs/m2. If in doubt about this conduct a structural survey, or your builder.
How deep is your system?
Allow 120mm for the build up, however this can be deeper to suit requirements.
My roof is pitched, will it take a greenroof?
We can comfortably green any roof up to 15º without additional support. However, any roof at a greater pitch than this will need to be assessed on a project by project basis. In theory it is possible to green a roof up to 30º.
Will my greenroof need to be watered?
Yes! Sedums are very resilient, and will survive dry weather extremely well, however for the first year and during any extended dry periods, watering will only benefit the plants. Ideally harvested water is the best option.
What plant varieties can I use?
Sky-Garden Greenroofs specialise in sedum blanket, planted with 8 sedum varieties, these have proven their drought and shade tolerance. You can, however, include in your planting schemes herbs such as thyme or marjoram, small bulbs like narcissi or crocus, or simply a very small scattering of wildflower seeds. Mosses and lichens will also succeed on most greenroofs. Don’t worry if a plant doesn’t seem to take, try others instead.
Is a greenroof maintenance free?
No greenroof is maintenance free, it is a living addition to your building and will need to be monitored and irrigated. We suggest weeding twice per year, once in the spring or summer and once in autumn or winter. This is to manage any invasive weeds and clearing of plant debris from guttering.
Are greenroofs always green?
No. Through-out the winter a greenroof is reliably green however, during spring summer and autumn, shades of red, yellow, blue, white and purples combine to provide a changing tapestry of colours.
Do I need a root barrier?
If you are using an EPDM or similar waterproof layer that includes an in-organic root resitant barrier like polyethylene or copper then an additional root barrier isnt necessary.
What is the difference between an extensive and intensive greenroof?
In short an extensive is a light weight, low growing mat of plants, designed to cover the roof deck with an ecological blanket.
An intensive greenroof requires deeper growing medium to support a wide variety of plants and turf. Features such as paving, decking lawns and high profile plants replicate a ground level garden.
